Working out your split times

Split times advice

Split times can seem like a complex business, but you can use this article and handy guide to work out your split times and get the low-down on negative splits.

What are split times?

Once you've got an idea of your finish time, you need to work out your 'split times'. Split times are simply the amount of time it takes you to complete any given section of the course – it could be each mile or kilometer, every 10k, or the first and second half of the race, depending on how much information you are willing to cope with.

Use your training

When projecting your finish time and splits, think about the times and speeds you have accomplished in your training. If you know, for example, that you have run 18 miles at a speed of nine minutes per mile in training – and felt shattered afterwards – let’s face it, it is unlikely that you’ll be able to run a further eight miles at the same speed on race day. But slowing your pace by an extra 30-60 seconds a mile will make the race far more comfortable, and your likelihood of success greater. If this is your first marathon, be conservative in your target – the idea is to complete, not compete.

Once you have established your target time, calculate what that equates to in terms of consistent split times for each mile (bearing in mind that you will undoubtedly be slower on the first two or three miles, as you jostle for space with the thousands of other runners). For more information, see the box below to find out how to convert your target time into splits.

Negative splits

Many experts advocate a ‘negative split’ for marathon running, in which you aim to run the second half of the race slightly faster than the first half. Whether you go for a negative split or even splits, you certainly don’t want to be slowing down as the miles pass – a sure recipe for hitting the dreaded wall.

Working out your split times: A guide

Convert your target time to minutes, then divide by 26.2. (If you want km splits instead, you'll need to divide your target time by 42.165 instead). You’ll end up with a 'decimal' number, which you then need to convert to minutes and seconds to give you a split time for each mile.